Artificial tooth



- Feb. 27, 1945. w. D. RABER 2,370,488

ARTIFICIAL TOOTH Filed March 8, 1943 Patented Feb. 27, 1945 UNITEDSTATES QFFICE I a I r 2,370,488"

ARTIEIGI-ALJIEQQIIJH. WaIter D. Raber, Chicago, Ill; 7 Application March8. 194a seam. grant .(o1; sz-s) 2* Claims.

This inuention relates to iiriproveinents;v in, artificial teeth; andmore: particularly to a tooth hatmesnoyel meanaofJretentiOn. One obj ctis taprorLi-de as diatoriotooth of i strength and beauty and atooththat; really. presents: the ppearance of anatural tooth. .Heretoiorepinless. or die.- torieteeth havezbeenr; lacking instreneth atjvitalpoints,- notably attire denture.- basewith. theirs..- suit-j. that.breakages; are,- of." frequent occurrence. Thishas been, due; to faulty:retention; the; re .tention being; placedwholly or; mainlyin; thegingiual. part at. the tooth, resulting; in; such ex;- treme leveragethat: pressure; applied. elsewhere upon the tooth must result inbreakage: at: the point-on entry ofretention into the base of the tooth.

A further object, therefore, of the instant invention is to provideretention extending well into the incisal half of the tooth so that itis efliciently supported throughout the major portion of its area orextent with the result that a maximum amound of grinding at the gingivalor cervical end is readily possible without in any way less-' ening theretention efficiency and in this manner the formerly long present longleverage from any point of external tooth pressure to a point ofretention is greatly reduced and breakage likewise curtailed oreliminated.

A further object of the instant invention is to provide an artificialtooth having a multi -point or finger-like interlocking of the toothwith the base material combined with a post of moderate diameter whichtherefore affords the strength of a much larger post than actuallyotherwise must be used. This specific structure provides a tooth welladapted for use as the end tooth of a partial denture because of themulti-point support at the base of the post. This great supportpostefficiency is highly important because most denture base materials inuse today are of a brittle nature and become more brittle as the dentureages.

A still further object is to provide an artificial tooth of long lingualsurface with the attendant obvious advantages, as well as a tooth havinga wholly unobstructed exterior thus affording a long bite of maximumefllciency.

A still further object is to provide an artificial tooth of greatstrength at all points and one that due to its specific retention isadapted for use at any and all points of the denture, one that adaptsitself to overlapping as well as to positioning at any desired angle tothe eases. desired interfitting is. possible without weakening at: anypoint;.

With the foregoing: and" other objects. in view the; invention consistsin. the combination and arrangement-4dr" parts to. be hereinafter fullyde-,

scribed; pointed; out in the claims and: illustrated in the accompanyingdrawing which formsv apart on thisnatentzandrwhich- .1 is a. view inside; elevation of" a tooth embodying the present inventionillustrating: its

' applihation to thegum,.the;retention= post of:den;-

teeth adjoining and onewherein grinding to 65 'ture material filling:the, tooth: cavities; being Fig. 6 is a View similar to Fig. 5 but takenhorizontally through Fig. 3.

Fig. 7 is a view similar to Fig. 6 but illustrating a slightly modifiedform of tooth, and,

Fig. 8 is a view in elevational perspective of the plastic core or postformed in the tooth cavities.

Like reference characters denote corresponding parts throughout theseveral views.

The reference numeral I denotes the tooth that is formed with a largecavity 2 opening on the gingival side and extending substantiallycentrally well into the incisal half of the tooth, the lower bodyportion 3 terminating in the cavity base 4. The mouth of the cavity 2 isenlarged by the opposed recesses 5, 6 extending therefrom to the lateralfaces [3, I4 of the tooth substantially midway between the buccal orlabial and lingual sides, and by a recess 1 extending from said mouthapproxinfately midway between recesses 5, B lingually almost to thatface, said recess 1 diminishing in depth as it recedes from said cavitymouth.

Diverging from each other are the opposed twin undercut cavities 8, 8that register with the lower end of said cavity 2, said undercutcavities being of materially smaller diameter and extent than saidcavity 2 and extending from said cavity toward opposite incisal pointsof the tooth.

Also registering with said cavity 2 are the opposed cavities 9, 9, saidcavities 9, 9 being provided only in teeth of suflicient length torequire or make desirable a precautionary support.

In use the tooth is applied to the rubber or other material of which theplate is made while the material is in a plastic or semi-liquid state sothat the material will flow into the cavity 2, recesses 5, 6, 1 andcavities 9,9 and when hardened will form tooth retention engaging thetooth at many points. It will be noted that the recesses 5, 6, 1 form athree-prong tooth gripping and supporting means about the mouth of thecavity 2 while the diverging cavities 8, 8 form a wedgeshaped retentionseated well in the incisal half of the tooth and cooperating with themajor cavity and recesses to effectually resist breakage at the cervicalend of the toothas well as providing resistance to twisting anddistortion.

The major tooth cavities while of substantial size do not weaken thetooth structure as they are mainly disposed centrally and extend fromthe lap face II more than half the distance to the incisal edgeafiording, when filled with den.-

ture material, the maximum degree of denture retention. Referring now toFig. 7 only, the tooth is formed in this slightly modified form withoppositely disposed vertical recesses l0, 10a formed in the toothsurface approximately midway between the labial and lingual faces andretention.

In Fig. 8 the denture material received in the tooth cavities andrecesses is shown apart from the tooth and comprises the post 15, thethree fingers I6 and diverging prongs [1 which respectively occupy thecavity 2, recesses 5, 6, 1 and undercut cavities 8, 8.

I do not desire to limit my invention to the specific details ofconstruction and arrangement'as herein set forth, and consequently wishsaid first named cavity and extending therefrom to opposite faces of thetooth and with a third recess communicating with said first named cavitydisposed substantially at right angles to said opposed recesses, all ofsaid cavities and recesses receiving the denture plate base material inwhich the tooth is mounted.

2. An artificial tooth having a cavity extending from the lap face in anincisal direction throughout the major portion of the tooth, theinnermost end of said cavity being undercut to form .25 which recesse'salso receive denture material for" smaller communicating cavitiesdiverging from each other in the general direction of opposite terminalpoints of the incisal edge of the tooth. the lap face of the tooth beingformed with two opposed recesses communicating with said first namedcavity and with a thirdrecess communicating with said first named cavitydisposed sub.-

, stantially at right angles to said opposed recesses,

said cavities and recesses receiving the base material of the dentureplate in which the tooth is mounted. Y

WALTER D. RABER.

